Methods and apparatus to identify and credit media using ratios of media characteristics

ABSTRACT

Apparatus, systems, articles of manufacture, and methods to identify and credit media using ratios of media characteristics are disclosed herein. Example apparatus to identify media include at least one memory, instructions, and at least one processor to execute the instructions to: determine a first ratio based on a first time interval and a second time interval of a monitored media signal; determine a second ratio based on the second time interval and a third time interval of the monitored media signal; generate a first ratio signature based on the first and second ratios; and initiate transmission of the first ratio signature to a recipient that is to compare the first signature with a second ratio signature to identify the media.

RELATED APPLICATIONS

This patent arises from a continuation of U.S. patent application Ser.No. 17/322,446, entitled “METHODS AND APPARATUS TO IDENTIFY AND CREDITMEDIA USING RATIOS OF MEDIA CHARACTERISTICS,” which was filed on May 17,2021, which is a continuation of U.S. patent application Ser. No.17/027,380, entitled “METHODS AND APPARATUS TO IDENTIFY AND CREDIT MEDIAUSING RATIOS OF MEDIA CHARACTERISTICS,” which was filed on Sep. 21,2020, issued as U.S. Pat. No. 11,012,745, which is a continuation ofU.S. patent application Ser. No. 16/512,056, entitled “METHODS ANDAPPARATUS TO IDENTIFY AND CREDIT MEDIA USING RATIOS OF MEDIACHARACTERISTICS,” which was filed on Jul. 15, 2019, issued as U.S. Pat.No. 10,785,532, which is a continuation of U.S. patent application Ser.No. 16/055,829, entitled “METHODS AND APPARATUS TO IDENTIFY AND CREDITMEDIA USING RATIOS OF MEDIA CHARACTERISTICS,” which was filed on Aug. 6,2018, issued as U.S. Pat. No. 10,368,127 which is a continuation of U.S.patent application Ser. No. 15/234,904, entitled “METHODS AND APPARATUSTO IDENTIFY AND CREDIT MEDIA USING RATIOS OF MEDIA CHARACTERISTICS,”which was filed on Aug. 11, 2016, issued as U.S. Pat. No. 10,045,075,and which claims the benefit of U.S. Provisional Application Ser. No.62/296,940, entitled “METHODS AND APPARATUS TO IDENTIFY MEDIA USINGRATIOS OF MEDIA CHARACTERISTICS,” which was filed on Feb. 18, 2016. U.S.patent application Ser. No. 17/322,446, U.S. patent application Ser. No.17/027,380, U.S. patent application Ser. No. 16/512,056, U.S. patentapplication Ser. No. 16/055,829, U.S. patent application Ser. No.15/234,904 and U.S. Provisional Application Ser. No. 62/296,940 arehereby incorporated herein by reference in their entireties.

FIELD OF THE DISCLOSURE

This disclosure relates generally to media identification, and, moreparticularly, to methods and apparatus to identify and credit mediausing ratios of media characteristics.

BACKGROUND

In recent years, media playback devices have added features that changehow media is viewed, recorded, played back, etc. For example, some mediaplayback devices support time-compressed playback in which media can beplayed back at a rate that is faster than a normal playback rate.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an illustration of a first example media signal and atime-compressed version of the first example media signal.

FIG. 2 is an example environment including an example referencesignature generator, an example meter, and an example media manager toidentify and credit media from media signals.

FIG. 3 illustrates an example reference media signal from which theexample reference signature generator of FIG. 2 generates an examplereference ratio signature.

FIG. 4 is a table of time differences forming the example referenceratio signature representative of the example reference media signal ofFIG. 3 .

FIG. 5 illustrates an example monitored media signal from which theexample meter of FIG. 2 generates an example monitored media ratiosignature.

FIG. 6 is a table of time differences forming the example monitoredmedia ratio signature representative of the example monitored mediasignal of FIG. 5 .

FIG. 7 is a table of the reference time differences of FIG. 4 andcorresponding ratios of the reference time differences of FIG. 4 .

FIG. 8 is a table of the monitored time differences of FIG. 6 andcorresponding ratios of the monitored time differences of FIG. 6 .

FIG. 9 is a table matching the reference ratios of FIG. 7 to themonitored ratios of FIG. 8 .

FIG. 10 is a table of the time differences of FIG. 4 and correspondingtime differences of FIG. 6 having ratios matched according to FIG. 9 .

FIG. 11A illustrates example energy peaks of an example reference ratiosignature.

FIG. 11B illustrates example energy peaks of an example monitored mediaratio signature differing from the example reference ratio signature ofFIG. 11A.

FIG. 12A is an example flow diagram representative of examplemachine-readable instructions that may be executed to implement theexample reference signature generator of FIG. 2 .

FIG. 12B is an example flow diagram representative of examplemachine-readable instructions that may be executed to implement theexample meter of FIG. 2 .

FIGS. 13-15 are example flow diagrams representative of examplemachine-readable instructions that may be executed to implement theexample media manager of FIG. 2 .

FIG. 16 illustrates an example processor platform structured to executethe example machine-readable instructions of FIGS. 12A-15 to implementthe example reference signature generator, the example meter, and/or theexample media manager of FIG. 2 .

DETAILED DESCRIPTION

Modern media playback devices include features that allow a consumer towatch media at a faster rate than the rate at which the media wasoriginally recorded or broadcast. For example, media can be played-backat a rate thirty percent faster (e.g., 1.3×) than the original playbackrate (e.g., 1.0×).

Increasing the rate of media playback affects both the video and audioaspects of a presentation of the media. In terms of video frames, somevideo frames may be presented for a shorter duration. For example,instead of presenting 24 frames in 1 second (e.g. 24 frames per second(“fps”)), or 1 frame approximately every 0.04 seconds (e.g., theNational Television System Committee standard), the same 24 frames maybe presented in 0.70 seconds (e.g., 34 fps), or 1 frame approximatelyevery 0.03 seconds. Additionally or alternatively, video frames may beremoved entirely. For example, skipping every fourth video frame (e.g.,presenting three frames out of four) increases the playback rate to 1.5times the original playback rate. Whether video frames are removed orpresented for a shorter duration, the effect is increased motionthroughout the media.

In terms of audio, increasing the rate of media playback increases thefrequency of audio signals (e.g., at a 1.5 times original playback rate,a three-second sound is time-compressed to fit into two seconds). As aresult, the audio pitch increases and distorts the original sound. Toaccommodate the modifications caused by an increased media playbackrate, portions of the media may be removed and/or reprocessed such thatthe overall experience of the media played at an increased rate is notsignificantly altered from that of media played at the original playbackrate.

FIG. 1 illustrates a graph of an example original media signal 100 aabove an example time-compressed version 100 b of the same media signal.The example graph of FIG. 1 is a close up of the example original mediasignal 100 a and the example time-compressed signal 100 b to showdifferences at the millisecond level. The example original media signal100 a includes media portions 102, 104, 106, and 108. The exampletime-compression version 100 b includes corresponding media portions110, 112, 114, and 116. As illustrated in FIG. 1 , exampletime-compressed media portions 112 and 116 are time-compressed versionsof example original media portions 104 and 108 created by increasing theplayback speed of those original media portions, whereas exampletime-compressed media portion 110 is a time-compressed version ofexample original media portion 102 that has also been reprocessed and/orhad parts of media signal removed. Similarly, example media portion 114is a time-compressed version of example original media portion 106 thathas also been reprocessed and/or had parts of media signal removed.Thus, example media portions 102 and 106 differ substantially fromcorresponding media portions 110 and 114, whereas media portions 112 and116 are similar, but time-compressed versions of corresponding mediaportions 104 and 108.

Example methods and apparatus disclosed herein identify media in mannersindependent of the rate at which media is played back. For example, someexample methods and apparatus determine ratios from time intervalsbetween characteristics of media to generate signatures capable ofidentifying the media even after the media is compressed, reprocessed,and/or has had portions removed.

Example methods and apparatus disclosed herein identify firstcharacteristics associated with reference media. The example referencemedia may be media capable of being provided and presented via an outputdevice, such as, for example, a television, a radio, a computer, set topbox, over the top device, mobile device, or other known output device.In some examples, the first characteristics are zero crossings of anaudio or video reference signal corresponding to reference media. Insome examples, the first characteristics are energy peaks in thereference media signal corresponding to the reference media. The exampleenergy peaks may represent local maximum points in media waves (e.g., inthe frequency and/or time domain), points that satisfy an examplethreshold, logical high values in digital signals, and/or other notableexample characteristics associated with media signals. Some examplemethods and apparatus calculate a first time interval, or first delta,between a first one of the first characteristics and a second one of thefirst characteristics. Similarly, such example methods and apparatuscalculate a second time interval, or second delta, between the secondone of the first characteristics and a third one of the firstcharacteristics. In some examples, the example methods and apparatusgenerate a reference delta signature based on a plurality (e.g.,sequence) of such deltas between characteristics of the media signal.

In some examples, the example methods and apparatus determine a ratiobetween the first delta and the second delta. Such example methods andapparatus determine additional ratios between the deltas of the mediasignal. Such example methods and apparatus generate a reference ratiosignature (also referred to herein as a reference time-compressedsignature) based on a plurality (e.g., sequence) of such ratios ofdeltas between characteristics of the media signal for subsequentidentification. Such example methods and apparatus disclosed hereingenerate such reference ratio signatures for a reference library ofbroadcast media and store the reference ratio signatures in an exampledatabase for future retrieval, matching, and identification of the mediaassociated with a corresponding signature.

Additionally, some example methods and apparatus disclosed hereinidentify second characteristics associated with monitored media (e.g.,media monitored by a metering device, also referred to herein as ameter) presented by an example output device. As similarly disclosedabove, some example methods and apparatus disclosed herein generate amonitored media delta signature for the monitored media. Some examplemethods and apparatus disclosed herein generate a monitored media ratiosignature (also referred to herein as a monitored signal time-compressedsignature) for the monitored media based on sequences of ratios of timedifferences between the identified second characteristics, as disclosedabove and in further detail below. In some example methods andapparatus, the meter reports such monitored media signatures to anaudience measurement entity (“AME”), which compares the examplemonitored media ratio signature to a plurality of reference ratiosignatures within the example database for matches. When the examplemonitored media ratio signature matches, or substantially matches, oneof the plurality of reference ratio signatures within the exampledatabase, such example methods and apparatus disclosed herein identifythe example monitored media based on the example matching referenceratio signature within the example database.

Some disclosed example methods and apparatus further identify atime-compression factor, if any, by dividing deltas associated with theexample matching reference ratio signature by corresponding deltasassociated with the example monitored media ratio signature. In someexamples, the example methods and apparatus determine there is notime-compression when the time-compression factor is equal to one. Insome examples where the time-compression factor is greater than one, theexample methods and apparatus determine the monitored media waspresented at a rate faster than a normal playback rate. In some exampleswhere the time-compression factor is less than one, the example methodsand apparatus determine the monitored media was presented at a rateslower than a normal playback rate. In some examples disclosed herein,the playback rate of the monitored media is associated with thetime-compression factor.

Some example methods and apparatus disclosed herein determine a durationthat the monitored media was presented. Some such example methods andapparatus determine the amount of time to credit the monitored media bymultiplying the duration of the monitored media by the time-compressionfactor (e.g., determined by dividing the deltas associated with thematching reference ratio signature by the corresponding deltasassociated with the monitored media ratio signature). In some examples,an example apparatus is located to perform disclosed example methodson-site (e.g., corresponding to a meter in proximity to the exampleoutput device). In some examples, an example apparatus is located toperform disclosed example methods off-site (e.g., data from the metermonitoring the example output device is reported to an AME's centralprocessing facility for analysis).

FIG. 2 is an example environment including an example referencesignature generator 200, an example meter 202, and an example mediamanager 204 to identify and credit media. In the illustrated example,the example reference signature generator 200 is separate from theexample media manager 204. In some examples, the example referencesignature generator 200 and the example media manager 204 may becombined.

The example reference signature generator 200 generates reference ratiosignatures from reference media such that the reference media is capableof subsequent identification based on the example reference ratiosignatures. Some example methods of identification include audiowatermarking and signature based techniques. Audio watermarking is atechnique used to identify media such as television broadcasts, radiobroadcasts, advertisements (television and/or radio), downloaded media,streaming media, prepackaged media, etc. Existing audio watermarkingtechniques identify media by embedding one or more audio codes (e.g.,one or more watermarks), such as media identifying information and/or anidentifier that may be mapped to media identifying information, into anaudio and/or video component. In some examples, the audio or videocomponent is selected to have a signal characteristic sufficient to hidethe watermark. As used herein, the terms “code” or “watermark” are usedinterchangeably and are defined to mean any identification information(e.g., an identifier) that may be inserted or embedded in the audio orvideo of media (e.g., a program or advertisement) for the purpose ofidentifying the media or for another purpose such as tuning (e.g., apacket identifying header). As used herein “media” refers to audioand/or visual (still or moving) content and/or advertisements. Toidentify watermarked media, the watermark(s) are extracted and used toaccess a table of reference watermarks that are mapped to mediaidentifying information.

Unlike media monitoring techniques based on codes and/or watermarksincluded with and/or embedded in the monitored media, fingerprint orsignature-based media monitoring techniques generally use one or moreinherent characteristics of the monitored media during a monitoring timeinterval to generate a substantially unique proxy for the media. Such aproxy is referred to as a signature or fingerprint, and can take anyform (e.g., a series of digital values, a waveform, etc.) representativeof any aspect(s) of the media signal(s)(e.g., the audio and/or videosignals forming the media presentation being monitored). A signature maybe a series of signatures collected in series over a time interval. Agood signature is repeatable when processing the same mediapresentation, but is unique relative to other (e.g., different)presentations of other (e.g., different) media. Accordingly, the term“fingerprint” and “signature” are used interchangeably herein and aredefined herein to mean a proxy for identifying media that is generatedfrom one or more inherent characteristics of the media.

Signature-based media monitoring generally involves determining (e.g.,generating and/or collecting) signature(s) representative of a mediasignal (e.g., an audio signal and/or a video signal) output by amonitored media device and comparing the monitored signature(s) to oneor more references signatures corresponding to known (e.g., reference)media sources. Various comparison criteria, such as a cross-correlationvalue, a Hamming distance, etc., can be evaluated to determine whether amonitored signature matches a particular reference signature. When amatch between the monitored signature and one of the referencesignatures is found, the monitored media can be identified ascorresponding to the particular reference media represented by thereference signature that with matched the monitored signature. Becauseattributes, such as an identifier of the media, a presentation time, abroadcast channel, etc., are collected for the reference signature,these attributes may then be associated with the monitored media whosemonitored signature matched the reference signature. Example systems foridentifying media based on codes and/or signatures are long known andwere first disclosed in Thomas, U.S. Pat. No. 5,481,294, which is herebyincorporated by reference in its entirety.

The example reference signature generator 200 of FIG. 2 includes anexample media characterizer 206, an example delta calculator 208, and anexample signature generator 210. The example media characterizer 206identifies characteristics of an example reference media signal. Forexample, the example media characterizer 206 identifies temporalcharacteristics of the example reference media signal, such as, forexample, times (e.g., timestamps, start time, stop time, duration),local peak signal magnitudes satisfying an example threshold, zerocrossings, logical highs, logical lows, integrations and/or derivativesthereof, or other known characteristics of the example media signal. Theexample media characterizer 206 may include a clock to keep track ofactual time independent of the time associated with the reference mediasignals.

The example delta calculator 208 determines a time interval or deltadTr(1) between adjacent temporal characteristics identified by theexample media characterizer 206. The example delta calculator 208determines one or more deltas dTr(2), dTr(3), dTr(4), dTr(5), dTr(6),dTr(7), dTr(8) for generation of a reference delta signature as furtherdisclosed below. The example delta calculator 208 additionallydetermines ratios dRr(1), dRr(2), dRr(3), dRr(4), dRr(5), dRr(6), dRr(7)between identified deltas dTr(1), dTr(2), dTr(3), dTr(4), dTr(5),dTr(6), dTr(7), dTr(8) of the reference media signal for generation of areference ratio signature as further disclosed below. For example, theexample delta calculator 208 determines a ratio between a first deltadTr(1) and a nearest delta dTr(2), (e.g., dTr(1)/dTr(2) or, moregenerally, dTr(n)/dTr(n+1)). Of course, the example delta calculator 208may determine alternative ratios, such as, for example, ratios between afirst delta and a second nearest delta (e.g., dTr(1)/dTr(3) or, moregenerally, dTr(n)/dTr(n+2)), ratios between a first delta dTr(1) and acombination of the first delta dTr(1) and the nearest delta dTr(2)(e.g., dTr(1)/(dTr(1)+dTr(2) or, more generally,dTr(n)/(dTr(n)+dTr(n+1)), etc.

In some examples, the example signature generator 210 combines aplurality (e.g., sequence) of the deltas determined for a referencemedia signal into a reference delta signature representative of thatmedia signal. In some examples, the example signature generator 210 alsocombines a plurality (e.g., sequence) of the ratios determined for thereference media signal into a reference time-compressed or ratiosignature representative of the media signal. The example signaturegenerator 210 transmits (e.g., via a network) generated reference deltasignatures and/or corresponding reference ratio signatures to an examplereference signature database 211. In some examples, the examplesignature generator 210 transmits (e.g., via a network) the generatedreference delta signatures and/or corresponding reference ratiosignatures to the example media manager 204. Additionally oralternatively, the example media manager 204 may generate the referenceratio signatures based on the deltas calculated by the example deltacalculator 208 and/or the reference delta signatures generated by theexample signature generator 210.

The example reference signature database 211 is a storage devicecontaining example reference delta signatures and/or correspondingreference ratio signatures generated by the example reference signaturegenerator 200. The example reference delta signatures and/orcorresponding reference ratio signatures stored in the example referencesignature database 211 are associated with the respective referencemedia in such a way to subsequently identify the reference media basedon the example reference delta signatures and/or corresponding referenceratio signatures.

The example meter 202 may be a local meter in proximity with an outputdevice to analyze media signals and report the results to a centralfacility. In some examples, the example meter 202 is similar to theexample reference signature generator 200 and includes an example mediacharacterizer 212, an example delta calculator 214, and an examplesignature generator 216. In some example, the example meter 202 receivesa monitored media signal to meter, monitor, characterize, and generate amonitored media ratio signature therefrom, similarly to the examplereference signature generator 200. The example meter 202 may be one of aplurality of example meters 202 distributed around a population (e.g., apanel) to monitor media presented to the population (e.g., panelists).In some examples, the example meter 202 monitors media at a householdlevel. In some examples, the example meter 202 monitors media at anindividual level.

The example media characterizer 212 identifies characteristics of anexample monitored media signal. For example, the example mediacharacterizer 212 identifies temporal characteristics of the examplemonitored media signal, such as, for example, times (e.g., timestamps,start time, stop time, duration), local peak signal magnitudessatisfying an example threshold, zero crossings, logical highs, logicallows, integrations and/or derivatives thereof, or other knowncharacteristics of the example media signal. The example mediacharacterizer 212 may include a clock to keep track of actual timeindependent of the time associated with the monitored media signals. Insome examples, the media characterizer 212 transmits mediacharacteristics to the example media manager 204.

The example delta calculator 214 determines a delta dTm(1) from adjacentidentified temporal characteristics identified by the mediacharacterizer 212. The example delta calculator 214 determines one ormore deltas dTm(2), dTm(3), dTm(4), dTm(5), dTm(6), dTm(7), dTm(8) in asimilar manner for generation of a monitored media delta signature. Insome examples, the example delta calculator 214 additionally determinesratios dRm(1), dRm(2), dRm(3), dRm(4), dRm(5), dRm(6), dRm(7) betweenidentified deltas dTm(1), dTm(2), dTm(3), dTm(4), dTm(5), dTm(6),dTm(7), dTm(8), etc. of the monitored media signal for generation of amonitored media ratio signature. For example, the example deltacalculator 214 determines a ratio between a first delta dTm(1) and anearest delta dTm(2), (e.g., dTm(1)/dTm(2) or, more generally,dTm(n)/dTm(n+1)). Of course, the example delta calculator 214 maydetermine alternative ratios, such as, for example, ratios between afirst delta and a second nearest delta (e.g., dTm(1)/dTm(3) or, moregenerally, dTm(n)/dTm(n+2)), ratios between a first delta dTm(1) and acombination of the first delta dTm(1) and the nearest delta dTm(2)(e.g., dTm(1)/(dTm(1)+dTm(2) or, more generally,dTm(n)/(dTm(n)+dTm(n+1)), etc.

The example signature generator 216 combines (e.g., groups) a plurality(e.g., sequence) of the deltas determined for a monitored media signalinto a monitored media delta signature representative of that mediasignal. The example signature generator 216 also combines (e.g., groups)a plurality (e.g., sequence) of the ratios determined for a monitoredmedia signal into a monitored media ratio signature representative ofthat media signal. In some examples, the example signature generator 216transmits generated monitored media delta signatures and/orcorresponding monitored media ratio signatures to the example mediamanager 204 via a network 217 (e.g., cellular network, the Internet,local-area network, etc.). Additionally or alternatively, the examplemedia manager 204 may generate the monitored media ratio signaturesbased on deltas calculated by the example delta calculator 214 andforming the monitored media delta signatures reported by the meter 202.

The example media manager 204 includes an example signature receiver218, an example delta extractor 220, an example signature comparator222, an example media identifier 224, an example multiplier identifier226, and an example media creditor 228.

The example signature receiver 218 obtains reference ratio signaturesfrom the example reference signature database 211 and/or monitored mediaratio signatures from the example meter 202. In some examples, theexample signature receiver 218 obtains reference delta signatures fromthe example reference signature database 211 and/or monitored mediadelta signatures from the example meter 202. In some examples, theexample signature receiver 218 sends reference delta/ratio signaturesand monitored media delta/ratio signatures to the example signaturecomparator 222 for comparison and signature matching.

In some examples, the example meter 202 determines the monitored ratiosand/or a monitored media ratio signature based on the monitored ratiosand sends the monitored ratios and/or monitored media ratio signature tothe example media manager 204. In some examples, the example meter 202sends the monitored deltas and/or a monitored media delta signaturebased on the monitored deltas to the example media manager 204. In suchexamples, the delta extractor 220 extracts deltas dTm(1), dTm(2),dTm(3), dTm(4), dTm(5), dTm(6), dTm(7), dTm(8) sent from the examplemeter 202 and generates a monitored media ratio signature. For example,the delta extractor 220 generates ratios dRm(1), dRm(2), dRm(3), dRm(4),dRm(5), dRm(6), dRm(7) based on the extracted deltas. The example deltaextractor 220 generates ratios and/or ratio signatures as discussed inconnection with the example delta calculator 208 and/or the exampledelta calculator 214. Accordingly, such description will not be repeatedand the interested reader is referred to the corresponding descriptionin connection with the example delta calculator 208 and/or the exampledelta calculator 214. In such examples, the delta extractor 220transmits the monitored media ratio signature to the example signaturecomparator 222.

In some examples, in response to receiving a monitored media ratiosignature, the example signature comparator 222 searches the examplereference signature database 211 for reference ratio signatures matchingthe example monitored media ratio signature. The example signaturecomparator 210 utilizes the ratios that make up the respective ratiosignatures to identify matches. For example, the example signaturecomparator 210 may identify a match between a reference ratio signatureand a monitored media ratio signature when the corresponding ratiosbetween the two signatures are identical, substantially similar, match athreshold number of times, etc.

The example media identifier 224 identifies a reference media associatedwith a reference ratio signature when the example signature comparator222 identifies the reference ratio signature as a match to the monitoredmedia ratio signature. The example media identifier 212 additionallyassociates the identified reference media with the monitored media forsubsequent crediting.

In some examples, the example delta extractor 220 extracts deltas fromratios matched by the example signature comparator 222 in order todetermine a time-compression factor or multiplier M_(TC) (if any) thatwas applied to the monitored media signal. The example multiplieridentifier 226 determines the multiplier by dividing the deltasassociated with the ratios from the reference ratio signature thatmatches the monitored media ratio signature by the corresponding deltasassociated with the ratios from the monitored media ratio signature thatmatch the reference ratio signature. Additionally or alternatively, theexample multiplier identifier 226 may determine the example multiplierby dividing an amount of media presented (e.g., the difference betweentimestamps of media) by the amount of time for which the media waspresented. In some examples, the example multiplier identifier 226identifies the duration of the monitored media (e.g., from the examplemedia characterizer 212) and applies the multiplier to the duration todetermine a crediting duration.

The example media creditor 228 receives the media identification fromthe example media identifier 224 and combines it with the creditingduration determined by the example multiplier identifier 226 todetermine what was presented and for how long, and to credit the same.

The example reference signature generator 200, the example media manager204, and the example reference signature database 211 may be operated byan example AME 230. In some examples, the example media manager 204 islocated at a central facility, while the example meter 202 is located ina different location (e.g., in a panelist's home).

In operation, the example reference signature generator 200 receivesreference media signals and generates reference signatures (e.g.,reference delta and/or ratio signatures) from the reference mediasignals to associate media with reference signatures. Additionally, theexample meter 202 receives monitored media signals, generates signatures(e.g., monitored media delta and/or ratio signatures) for the monitoredmedia, and sends the monitored media ratio signatures and othermonitored media information via a network, such as, for example, theInternet, to the example media manager 204. The example media manager204 compares monitored media ratio signatures to reference ratiosignatures to identify and credit the monitored media based on referencemedia.

With reference to FIGS. 3-10 , the example media characterizer 206 ofthe example reference signature generator 200 receives an examplereference media signal 300. The example delta calculator 208 determinesreference time intervals or reference deltas dTr(1), dTr(2), dTr(3),dTr(4), dTr(5), dTr(6), dTr(7), dTr(8) (FIG. 3 ) between characteristicsof the example reference media signal 300 identified by the examplemedia characterizer 206. In some examples wherein the examplecharacterizer 206 identifies local peak signal magnitudes, the exampledelta calculator 208 determines reference deltas between a first peaksignal magnitude 302 and a nearest peak signal magnitude 304, and so on.Example values of the reference deltas determined by the example deltacalculator 208 for the example reference media signal 300 are shown intable 400 of FIG. 4 . For example, the reference deltas between adjacentidentified characteristics for the example reference media signal 300may be 0.6000, 0.2000, 0.5000, 0.7000, 0.3000, 0.4000, 0.5000, 0.8000,etc., as shown in FIG. 4 .

As shown in FIG. 5 , the example meter 202 determines characteristics ofan example monitored media signal 500, such as peak magnitudes 502, 504.The example meter 202 determines a metered time interval or metereddelta dTm(1) from the peak magnitudes 502, 504 of the example monitoredmedia signal 500. The example meter 202 determines monitored deltasdTm(2), dTm(3), dTm(4), dTm(5), dTm(6), dTm(7), dTm(8), etc. (FIG. 5 ),between subsequent adjacent identified characteristics in a similarmanner. Example values of the monitored deltas determined by the exampledelta calculator 214 for the example monitored media signal 500 areshown in table 600 of FIG. 6 . For example, the monitored media deltasbetween adjacent identified characteristics for the example monitoredmedia signal 500 may be 0.3083, 0.3927, 0.4874, 0.4286, 0.1426, 0.3571,0.5000, 0.2143, etc., as shown in FIG. 6 .

As shown in table 700 of FIG. 7 , the example delta calculator 208 ofthe example reference signature generator 200 determines referenceratios dRr(1), dRr(2), dRr(3), dRr(4), dRr(5), dRr(6), dRr(7) from theadjacent reference deltas dTr(1), dTr(2), dTr(3), dTr(4), dTr(5),dTr(6), dTr(7), dTr(8) for the reference ratio signature. For example,dRr(1)=dTr(1)/dTr(2)=0.6000/0.2000=3.000;dRr(2)=dTr(2)/dTr(3)=0.2000/0.5000=0.4000; etc. (FIG. 7 ). An examplereference ratio signature for the example reference media signal 300 maybe a sequence of ratios determined by the example delta calculator 214,such as 3.000, 0.4000, 0.7143, 2.3333, 0.7500, 0.8000, 0.6250, etc., asillustrated in FIG. 9 .

As shown in table 800 of FIG. 8 , the example delta calculator 214 ofthe example meter 202 determines monitored ratios dRm(1), dRm(2),dRm(3), dRm(4), dRm(5), dRm(6), dRm(7) from the adjacent monitoreddeltas dTm(1), dTm(2), dTm(3), dTm(4), dTm(5), dTm(6), dTm(7), dTm(8)for the monitored media ratio signature. For example,dRm(4)=dTm(4)/dTm(5)=0.4286/0.1426=3.000;dRm(5)=dTm(5)/dTm(6)=0.1426/0.3571=0.4000; etc. (FIG. 8 ). An examplemonitored media ratio signature for the example monitored media signal500 may be 0.7851, 0.8057, 1.1372, 3.000, 0.4000, 0.7143, 2.3333, etc.as illustrated in FIG. 9 .

In some examples, the example signature generator 216 of the examplemeter 202 generates a monitored media ratio signature based on themonitored deltas and sends (e.g., via the network 217) the monitoredmedia ratio signature to the example media manager 204. In someexamples, the example signature generator 216 of the example meter 202generates a monitored media ratio signature based on the monitoredratios and sends (e.g., via the network 217) the monitored media ratiosignature to the example media manager 204.

As shown in table 900 in FIG. 9 , upon receiving the monitored mediaratio signature, the example signature comparator 222 of the examplemedia manager 204 searches the example reference signature database 211for a reference ratio signature matching the example monitored mediaratio signature. For example, the example monitored media ratiosignature with ratios dRm(4), dRm(5), etc. identified in FIG. 8 iscompared to the example reference ratio signature with ratios dRr(1),dRr(2), etc. identified in FIG. 7 . In such examples, the examplesignature comparator 222 identifies that the example monitored mediaratio signature matches one or more ratios in the example referenceratio signature (e.g., dRm(4) matches dRr(1) and dRm(5) matches dRr(2)).

Thereafter, the example delta extractor 220 identifies the correspondingdeltas (e.g., dTr(1), dTr(2), dTr(3), dTr(4), dTr(5) and dTm(4), dTm(5),dTm(6), dTm(7), dTm(8)) associated with matching ratios. As shown inFIGS. 9-10 , the first ratio from the reference ratio signature may notmatch with the first ratio from the monitored media signal. However, atleast a portion of the ratios that make up the reference ratio signatureshould be identified within the ratios of the monitored media ratiosignature if they are the same media. In other words, the ratios of themonitored media ratio signature will eventually align with the ratios inthe reference ratio signature, as shown in FIG. 9 , when the monitoredmedia is the same as a reference media.

The example multiplier identifier 226 identifies whether the monitoredmedia is time-compressed (and by how much) by dividing the matchingreference deltas by the matching monitored media deltas (e.g.,dTr(1)/dTm(4), dTr(2)/dTm(5), dTr(3)/dTm(6), dTr(4)/dTm(7),dTr(5)/dTm(8)) (FIG. 10 ). For example, the example multiplieridentifier 214 identifies the multiplier:M_(TC)(1)=dTr(1)/dTm(4)=0.6000/0.4286=1.39,M_(TC)(2)=dTr(2)/dTm(5)=0.2000/0.1426=1.40, etc. In the illustratedexample, the M_(TC) is consistently 1.40, however, the M_(TC) may changethroughout a media signal (e.g., depending on user operation of theoutput device through which media is monitored and/or the meter). Forexample, M_(TC)(1) may be 1.4, while M_(TC)(2) is 1.0 and M_(TC)(3) is1.3. The example multiplier identifier 226 can determine the multiplierover time (e.g., on a second-to-second or minute-to-minute basis) or maybe event driven (e.g., upon a signal that the playback rate haschanged).

In some examples, as shown in FIGS. 11A-11B, an example reference mediasignal 1100 slightly differs from an example monitored media signal1110. In some examples, either the example reference media signal 1100or the example monitored media signal 1110 are altered, such as byexternal circumstances (e.g., equalization, volume fluctuation, noisecancellation, interference, etc.). In the illustrated example, anexample characteristic (e.g., energy peak) 1105 from example referencemedia signal 1100 was not metered (e.g., missing in the correspondingmonitored media signal) in the example monitored media signal 1110, asindicated by reference numeral 1115. Of course, the example referencemedia signal 1100 could also have missing characteristics. When missingcharacteristics occur in the example monitored media signal 1110, thecorresponding deltas (and delta signatures) and the corresponding ratios(and ratio signatures) are likewise affected.

For example, as shown in FIGS. 11A-11B, the third delta for the examplemonitored media signal 1110 would be equal to the combination of thethird and fourth deltas for the example reference signal 1100 when theexample monitored media signal 1110 is missing the energy peak thatshould have appeared at reference numeral 1115. When the deltas differ,the corresponding delta signatures will differ, potentially leading tofalse negatives in delta signature matching. Also when the deltasdiffer, the resulting ratios of the deltas would also differ,potentially leading to false negatives in ratio signature matching.

In some such examples, as further discussed in conjunction with FIG. 15, the example signature comparator 210 utilizes a first level referenceratio signature to match ratios in the monitored media ratio signatureup until an error occurs (e.g., the deltas and/or the ratios of themonitored media ratio signature do not match the reference ratiosignature). In some examples, the first level reference ratio signatureincludes reference ratios defined as: dTr(n)/(dTr(n)+dTr(n+1)). This iscompared to a monitored media ratio signature that includes monitoredmedia ratios defined as dTm(n)/(dTm(n)+dTm(n+1)). Where there is anerror in the monitored media ratio signature (e.g., due to a missingenergy peak in the monitored media signal), the example signaturecomparator 210 utilizes a second level reference ratio signature tomatch ratios in the monitored media ratio signature to ratios in thereference ratio signatures. In some examples, the second level referenceratio signature includes ratios defined as:dTr(n)/(dTr(n)+dTr(n+1)+dTr(n+2)). This is compared to the monitoredmedia ratio signature that includes ratios defined asdTm(n)/(dTm(n)+dTm(n+1)).

As shown in FIGS. 11A-11B, an example ratio from the second levelreference ratio signature at point dRr(2) would bedTr(2)/(dTr(2)+dTr(3)+dTr(4)) while an example ratio from the monitoredmedia ratio signature at point dRm(2) would be dTm(2)/(dTm(2)+dTm(3)).In the illustrated example, these ratios would be the same even thoughthe monitored media signal is missing a characteristic (e.g., an energypeak). Additional levels of ratios may be used to correct for additionalerrors, without departing from the scope of the present disclosure.

In some examples, an extra characteristic (e.g., energy peak) appears inthe monitored media signal 1110. Of course, an extra characteristic mayappear in the reference media signal 1100. In examples wherein theexample monitored media signal 1110 includes an extra characteristic,the example signature comparator 222 may utilize a first level monitoredmedia ratio signature to match ratios in the monitored media ratiosignature to reference ratio signatures. In some examples, the firstlevel monitored media ratio signature includes ratios defined as:dTm(n)/(dTm(n)+dTm(n+1)). This is compared to a reference ratiosignature that includes ratios defined as dTr(n)/(dTr(n)+dTr(n+1)).Similarly as disclosed above, the example signature comparator 222 mayutilize a second level monitored media ratio signature to match ratiosin the monitored media ratio signature. In some examples, the secondlevel monitored media ratio signature includes ratios defined as:dTm(n)/(dTm(n)+dTm(n+1)+dTm(n+2)). This is compared to the referenceratio signature that includes ratios defined asdTr(n)/(dTr(n)+dTr(n+1)).

An example ratio from the second level monitored media ratio signatureat point dRm(2) would be dTm(2)/(dTm(2)+dTm(3)+dTm(4)) while an exampleratio from the reference ratio signature at dRr(2) would bedTr(2)/(dTr(2)+dTr(3)). In such an example, the reference delta dTr(3)is equal to dTm(3)+dTm(4). These methods allow the example signaturecomparator 222 to match monitored media ratio signatures to referenceratio signatures when errors occur in the monitored media signal. Ofcourse, the methods and apparatus disclosed herein can identify matchesfor monitored media signals with any combinations of missing or extracharacteristics.

As disclosed above, missing and/or extra characteristics may appear inthe example reference media signal 1100 and/or the example monitoredmedia signal 1110. In examples wherein the example reference mediasignal 1100 (or example monitored media signal 1110) includes an extracharacteristic, it may appear that the example monitored media signal1110 (or example reference media signal 1100) is missing that extracharacteristic. In examples wherein the example reference media signal1100 (or example monitored media signal 1110) is missing acharacteristic, it may appear that the example monitored media signal1110 (or example reference media signal 1100) includes an extracharacteristic. However, the example signature comparator 222 canidentify matches between the example reference media ratio signature andthe example monitored media ratio signature by utilizing the multiplelevel definitions of respective reference media ratio signatures ormonitored media ratio signatures. For example, when the reference mediasignal is missing a characteristic, the example signature comparator 222utilizes the second level monitored media ratio signature and when themonitored media signal is missing a characteristic, the examplesignature comparator 222 utilizes the second level reference media ratiosignature. Similarly, when the reference media signal has an extracharacteristic, the example signature comparator 222 utilizes the secondlevel reference ratio signature and when the monitored media signal hasan extra characteristic, the example signature comparator 222 utilizesthe second level monitored media ratio signature.

In some examples, the example meter 202 transmits monitored media deltasto the example media manager 204. In such examples, the signaturecomparator 222 of the example media manager 204 searches for referencedelta signatures matching the monitored media deltas. The examplesignature comparator 222 compares the monitored media deltas toreference deltas in the example reference signature database 211 formatches. If the example signature comparator 222 does not identify amatch, the example media manager 204 may determine that the monitoredmedia is associated with a time-compression factor or multiplier. Insuch examples, the example delta extractor 220 of the example mediamanager 204 multiplies the monitored media deltas by example multipliers(e.g., the example multipliers can be less than one, one, or greaterthan one and may be multiples of 0.01, 0.05. 0.1, etc.) to create aplurality of multiplier monitored media delta signatures (e.g., insteadof, or in addition to, using ratio signatures). For example, the examplemedia manager 204 may create a multiplier monitored media deltasignature with a 1.1× multiplier, a 0.95× multiplier, a 1.3× multiplier,etc.

Alternatively, the example delta extractor 220 may create the pluralityof multiplier monitored media delta signatures prior to searching forreference delta signatures matching the monitored media deltas.Thereafter, the example signature comparator 222 may search against theexample reference signature database 211 for reference delta signaturesmatching the monitored media deltas or any of the plurality ofmultiplier monitored media delta signatures.

In some examples, the matching of the plurality of multiplier monitoredmedia delta signatures may be performed in parallel. In some examples,the above-disclosed process may be performed iteratively (e.g., onemultiplier monitored media delta signature is compared to the referencesignature database at a time) until a match is found. In such examples,the matching conditions may be relaxed (e.g., only a threshold number ofdeltas need to match (e.g., 85%)). In some examples, the example meter202 may perform the application of the multipliers to the examplemonitored media deltas and transmit the same to the example mediamanager 204.

In some examples, the example media manager 204 creates a plurality ofreference delta signature databases based on the example referencesignature database 211. The example media manager 204 may applypre-determined time-compression multipliers to delta signatures in theexample reference signature database 211 to create multiplier referencedelta signature databases. For example, the example media manager 204may divide the deltas in the baseline reference delta signature withinthe example reference signature database 211 by example multipliers tocreate numerous multiplier reference delta signature databases storingrespective reference signatures having deltas that are time scaled bythe respective multipliers.

The example multipliers may be less than one, equal to one, or greaterthan one. For example, an example multiplier that is less than one maycorrespond to a decreased playback rate, and example multiplier that isequal to one may correspond to a normal playback rate, and an examplemultiplier greater than one may correspond to an increased playbackrate. The example multipliers may be multiples of 0.01, 0.05. 0.1, etc.

In such examples, the example meter 202 transmits monitored media deltas(e.g., a monitored media delta signature) to the example media manager204. In some such examples, the example signature comparator 222searches for reference delta signatures matching the monitored mediadeltas. The example signature comparator 222 compares the monitoredmedia deltas to reference deltas in the example reference signaturedatabase 211 for matches. If the example signature comparator 222 doesnot identify a match, the example media manager 204 determines that themonitored media is time-compressed. The example signature comparator 222may iteratively search through the example multiplier reference deltasignature databases storing reference delta signatures with differentlyscaled deltas until a match is found. Once a match is found, the examplemedia manager 204 may identify the multiplier and credit media asdescribed herein.

In some examples, the example delta extractor 220 may apply (e.g., bymultiplying or dividing) the example multipliers to the deltas in thebaseline reference delta signature within the example referencesignature database 211 to create numerous multiplier reference deltasignature databases storing respective reference signatures havingdeltas that are time scaled by the respective multipliers. In someexamples, the example media manager 204 may apply (e.g., by multiplyingor dividing) the example multipliers to the monitored media deltas tocreate a plurality of multiplier monitored media delta signatures.

While example manners of implementing the example reference signaturegenerator 200, the example meter 202, and/or the example media manager204 are illustrated in FIG. 2 , one or more of the elements, processesand/or devices illustrated in FIG. 2 may be combined, divided,re-arranged, omitted, eliminated and/or implemented in any other way.Further, the example media characterizer 206, the example deltacalculator 208, the example signature generator 210, and/or, moregenerally, the example reference signature generator 200 of FIG. 2 ; theexample media characterizer 212, the example delta calculator 214, theexample signature generator 216, and/or, more generally, the examplemeter 202 of FIG. 2 ; and the example signature receiver 218, theexample delta extractor 220, the example signature comparator 222, theexample media identifier 224, the example multiplier identifier 226, theexample media creditor 228, and/or, more generally, the example mediamanager 204 of FIG. 2 may be implemented by hardware, software, firmwareand/or any combination of hardware, software and/or firmware. Thus, forexample, any of the example media characterizer 206, the example deltacalculator 208, the example signature generator 210, and/or, moregenerally, the example reference signature generator 200 of FIG. 2 ; theexample media characterizer 212, the example delta calculator 214, theexample signature generator 216, and/or, more generally, the examplemeter 202 of FIG. 2 ; and the example signature receiver 218, theexample delta extractor 220, the example signature comparator 222, theexample media identifier 224, the example multiplier identifier 226, theexample media creditor 228, and/or, more generally, the example mediamanager 204 of FIG. 2 could be implemented by one or more analog ordigital circuit(s), logic circuits, programmable processor(s),application specific integrated circuit(s) (ASIC(s)), programmable logicdevice(s) (PLD(s)) and/or field programmable logic device(s) (FPLD(s)).When reading any of the apparatus or system claims of this patent tocover a purely software and/or firmware implementation, at least one ofthe example media characterizer 206, the example delta calculator 208,the example signature generator 210, and/or, more generally, the examplereference signature generator 200 of FIG. 2 ; the example mediacharacterizer 212, the example delta calculator 214, the examplesignature generator 216, and/or, more generally, the example meter 202of FIG. 2 ; and the example signature receiver 218, the example deltaextractor 220, the example signature comparator 222, the example mediaidentifier 224, the example multiplier identifier 226, the example mediacreditor 228, and/or, more generally, the example media manager 204 ofFIG. 2 is/are hereby expressly defined to include a tangible computerreadable storage device or storage disk such as a memory, a digitalversatile disk (DVD), a compact disk (CD), a Blu-ray disk, etc. storingthe software and/or firmware. Further still, the example referencesignature generator 200, the example meter 204, and/or the example mediamanager 204 may include one or more elements, processes and/or devicesin addition to, or instead of, those illustrated in FIG. 2 , and/or mayinclude more than one of any or all of the illustrated elements,processes and devices.

Flowcharts representative of example machine readable instructions forimplementing the example reference signature generator 200, the examplemeter 204, and/or the example media manager 204 of FIG. 2 are shown inFIGS. 12A-15 . In these example, the machine readable instructionscomprise programs for execution by a processor such as the processor1612 shown in the example processor platform 1600 discussed below inconnection with FIG. 16 . The programs may be embodied in softwarestored on a tangible computer readable storage medium such as a CD-ROM,a floppy disk, a hard drive, a digital versatile disk (DVD), a Blu-raydisk, or a memory associated with the processor 1612, but the entireprogram and/or parts thereof could alternatively be executed by a deviceother than the processor 1612 and/or embodied in firmware or dedicatedhardware. Further, although the example program is described withreference to the flowcharts illustrated in FIGS. 12A-15 , many othermethods of implementing the example media manager 200 may alternativelybe used. For example, the order of execution of the blocks may bechanged, and/or some of the blocks described may be changed, eliminated,or combined.

As mentioned above, the example processes of FIGS. 12A-15 may beimplemented using coded instructions (e.g., computer and/or machinereadable instructions) stored on a tangible computer readable storagemedium such as a hard disk drive, a flash memory, a read-only memory(ROM), a compact disk (CD), a digital versatile disk (DVD), a cache, arandom-access memory (RAM) and/or any other storage device or storagedisk in which information is stored for any duration (e.g., for extendedtime periods, permanently, for brief instances, for temporarilybuffering, and/or for caching of the information). As used herein, theterm tangible computer readable storage medium is expressly defined toinclude any type of computer readable storage device and/or storage diskand to exclude propagating signals and transmission media. As usedherein, “tangible computer readable storage medium” and “tangiblemachine readable storage medium” are used interchangeably. Additionallyor alternatively, the example processes of FIGS. 12A-15 may beimplemented using coded instructions (e.g., computer and/or machinereadable instructions) stored on a non-transitory computer and/ormachine readable medium such as a hard disk drive, a flash memory, aread-only memory, a compact disk, a digital versatile disk, a cache, arandom-access memory and/or any other storage device or storage disk inwhich information is stored for any duration (e.g., for extended timeperiods, permanently, for brief instances, for temporarily buffering,and/or for caching of the information). As used herein, the termnon-transitory computer readable storage medium is expressly defined toinclude any type of computer readable storage device and/or storage diskand to exclude propagating signals and transmission media. As usedherein, when the phrase “at least” is used as the transition term in apreamble of a claim, it is open-ended in the same manner as the term“comprising” is open ended.

FIG. 12A is an example flow diagram representative of examplemachine-readable instructions 1200 that may be executed to implement theexample reference signature generator 200 of FIG. 2 . At block 1202, theexample media characterizer 206 obtains and analyzes a reference mediasignal. The example reference media signal may be for signaturegeneration purposes, media identification purposes, media creditingpurposes, etc. In the illustrated example, the example mediacharacterizer 206 identifies media characteristics, such as, forexample, local maximum points of a waveform associated with thereference media signal (block 1204). The example delta calculator 208calculates a plurality of time intervals or deltas between the mediacharacteristics identified by the example media characterizer 206 atblock 1204 (block 1206). In response to determining the plurality ofdeltas, the example delta calculator 208 additionally calculates aplurality of ratios based on the plurality of deltas (block 1208). Asdisclosed herein, the ratios may be between a first delta and a nearestneighbor, between a first delta and a second nearest neighbor, betweeneven deltas, between odd deltas, etc. The example signature generator210 aggregates the plurality of ratios determined for the referencemedia signal to generate a reference ratio signature for the referencemedia represented by the reference media signal (block 1210).Thereafter, the example instructions 1200 cease. Numerous referenceratio signatures may be generated for a plurality of media in thismanner and may be stored in the reference signature database 211 forsubsequent media identification. In some examples where the exampleprogram 1200 is generating reference ratio signatures for media, theexample media signal may be quality controlled and the signaturegeneration may be performed in a controlled environment to avoidvariations in the signature generation.

FIG. 12B is an example flow diagram representative of examplemachine-readable instructions 1220 that may be executed to implement theexample meter 202 of FIG. 2 . At block 1222, the example mediacharacterizer 212 obtains and analyzes a monitored media signal (e.g., apotentially time-compressed media signal) from an example output device.In the illustrated example, the example media characterizer 212identifies media characteristics, such as, for example, local maximumpoints of a waveform associated with the monitored media signal (block1224). The example delta calculator 214 calculates a plurality of deltasbetween the monitored media characteristics identified by the examplemedia characterizer 212 in block 1224 (block 1226). In response todetermining the plurality of deltas, the example delta calculator 214additionally calculates a plurality of ratios based on the pluralitydeltas (block 1228). In some examples, the example signature generator216 aggregates the plurality of ratios determined for the monitoredmedia signal to generate a monitored media ratio signature for the mediarepresented by the monitored media signal (block 1230). The examplesignature generator 216 sends the example monitored media ratiosignature, media characteristics, and/or a monitored media deltasignature corresponding to the plurality of deltas to the example mediamanager 204 via the network 217 (block 1232). Thereafter, the exampleinstructions 1220 cease.

FIG. 13 is an example flow diagram representative of examplemachine-readable instructions 1300 that may be executed to implement theexample media manager of FIG. 2 to match monitored signatures toreference ratio signatures.

At block 1302, the example signature receiver 218 receives a monitoredmedia ratio signature from the example meter 202. In some examples, theexample delta extractor 220 extracts the monitored ratios from themonitored media ratio signature (block 1304). The example signaturecomparator 222 searches the example reference signature database 211 forreference ratio signatures with ratios matching the monitored ratios forthe monitored media signal (block 1306). In some examples the examplesignature comparator 222 searches for reference ratio signaturesmatching at least one of the monitored ratios, reference ratiosignatures matching a majority of the monitored ratios, reference ratiosignatures matching all of the monitored ratios, reference ratiosignatures matching a threshold number of the monitored ratios, etc.

If the example signature comparator 222 does not identify a referenceratio signature matching (e.g., identical, substantially similar, havinga threshold number of matching ratios, etc.) the monitored ratios (e.g.,the ratio signature generated for the monitored media signal) (block1308: NO), then control returns to block 1306. In some examples, theexample signature comparator 222 searches for identical matches first,then if no matches are found, the example signature comparator 222searches for substantially similar matches, then if no matches arefound, the example signature comparator 222 searches for a thresholdnumber of matching ratios.

If the example signature comparator 210 identifies a reference ratiosignature matching (e.g., identical, substantially similar, having athreshold number of matching ratios, etc.) the monitored ratios (e.g.,the ratio signature generated for the monitored media signal) (block1308: YES), then the example media identifier 224 determines that thereference media associated with the matching reference ratio signatureshould be associated with the monitored media signal. The example mediaidentifier 224 identifies the monitored media signal as being associatedwith the reference media associated with the matching reference ratiosignature (block 1310). Thereafter, the example instructions 1300 cease.

FIG. 14 is an example flow diagram representative of examplemachine-readable instructions 1400 that may be executed to implement theexample media manager 204 of FIG. 2 to credit identified media. In someexamples, the example instructions 1400 are executed subsequent toexample instructions 1200, 1220, and 1300. In some examples, exampleinstructions 1200, 1300, and 1400 may be executed concurrently inparallel.

As discussed herein, media may be presented at an increased playbackrate. If media is presented in this manner, the length of timeassociated with media consumption will be shorter than if the media waspresented at an original playback rate, even though the same media wasconsumed. To align media played at an increased rate with media playedat the original playback rate, the example program 1400 determines thetime-compression factor and/or the increased playback rate.

The example delta extractor 220 identifies a monitored media ratiosignature and a matching reference ratio signature identified by theexample signature comparator 222 via instructions 1300. The exampledelta extractor 220 identifies a first delta associated with thereference ratio signature (block 1402). In the illustrated example, thereference ratio signature is associated with a reference media signal,which has the original playback rate. The example delta extractor 220identifies a second delta associated with the monitored media ratiosignature (block 1404). In some examples, the first and second deltascorrespond to the first deltas used to compute the first ratios thatmatch in their respective signatures. For example, as previouslydisclosed in conjunction with FIGS. 9-10 , the first delta may be dTr(1)and the second delta may be dTm(4). To determine the multiplier M_(TC),the example multiplier identifier 226 divides the first delta by thesecond delta (e.g., dTr(1)/dTm(4)) (block 1406).

Additionally or alternatively, the example multiplier identifier 226 maydetermine the example multiplier by dividing an amount of mediapresented (e.g., the difference between timestamps of media) by theamount of time for which the media was presented. In some examples,media is presented at the original playback speed, presented at anincreased playback speed, and then returned to the original playbackspeed (or vice a versa), which potentially can lead to gaps increditing. In some examples, the example media creditor 228 may identifygaps in crediting and request media time stamps associated with thestart and stop times of the gap in crediting from the mediacharacterizer 212. The example media characterizer 212 determines theduration of the media that was presented during the gap in crediting bycomparing the time stamp of the media when the gap started and when thegap ended. For example, a gap in crediting may develop at minute 15 of amedia program and end at minute 45 of the media program. In suchexamples, the media characterizer 212 determines the duration of themedia presented to be 30 minutes of media. However, the example mediacharacterizer 212 may also determine, via the clock, that those 30minutes of media were presented in 20 minutes of time. Therefore, theexample multiplier identifier 226 can determine the example multiplierassociated with the gap in crediting by dividing the amount of mediapresented (e.g., 30 minutes) by the amount of time for which the mediawas presented (e.g., 20 minutes), or M_(TC)=30 min/20 min=1.5.Determining the multiplier (and thus a change in playback rate) in thismanner may be combined with current crediting techniques and/or thecrediting techniques disclosed herein.

If the example M_(TC) does not equal one (block 1408: NO), the examplemedia creditor 228 determines the monitored media signal istime-compressed media and obtains the duration of the monitored mediafrom the example media characterizer 212. The example media creditor 228multiplies the duration of the monitored media by the multiplier M_(TC)to determine the broadcast time for which to credit the monitored media(block 1410) and control proceeds to block 1412. However, if the exampleM_(TC) equals one (block 1408: YES), the example media creditor 228determines the monitored media signal is not time-compressed and controlproceeds to block 1412.

At block 1412, the example media creditor 228 communicates with theexample media identifier 224 to credit the media associated with themonitored media signal as having been presented for a determinedduration. In some examples wherein the monitored media signal istime-compressed, the example media creditor 228 credits the media asbeing presented for the duration determined in block 1410. In someexamples wherein the monitored media signal is not time-compressed(e.g., M_(TC)=1), the example media creditor 228 credits the media asbeing presented for the duration determined by the example mediacharacterizer 212. Alternatively, the example media creditor 228 candetermine the broadcast time for which to credit the example media bydetermining the amount of media presented through timestamp analysis, asdisclosed above. Thereafter, the example instructions 1400 cease.

FIG. 15 is an example flow diagram representative of examplemachine-readable instructions 1500 that may be executed to implement theexample signature comparator 222 of FIG. 2 to match signatures havingerrors to reference ratio signatures in the example reference signaturedatabase 211. As described above, the example signature comparator 222searches the example reference signature database 211 for referenceratio signatures matching the monitored ratios (e.g., the ratiosignature for the monitored media signal). In some examples, themonitored media signal is missing energy peaks, which leads to monitoredmedia deltas and ratios that do not match to the ratios in a referenceratio signature. While using a majority approach (e.g., does a majorityof monitored ratios match the reference ratio signature) can counteractthis possibility, the example instructions 1500 can reduce the number ofnon-matching ratios.

At block 1502, the example signature comparator 222 determines whetherthe plurality of ratios of the monitored media signal has an identicalmatch to a reference ratio signature. If so (block 1502: YES), theexample instructions 1500 cease. However, if the plurality of ratios ofthe monitored media signal do not match a reference ratio signatureexactly (block 1502: NO), control proceeds to block 1504. At block 1504,the example delta extractor 220 identifies each ratio in the monitoredmedia ratio signature and the reference ratio signature and thesignature comparator 222 compares them one by one. If the next monitoredmedia ratio matches the corresponding ratio in the reference ratiosignature (block 1504: YES), control proceeds to block 1506. At block1506, the example signature comparator 222 utilizes a first levelreference ratio signature to match ratios in the monitored media ratiosignature. In some examples, the first level reference ratio signatureincludes reference ratios defined as: dTr(n)/(dTr(n)+dTr(n+1)). This iscompared to a monitored media ratio signature that includes monitoredmedia ratios defined as dTm(n)/(dTm(n)+dTm(n+1)).

If there are more ratios (block 1508: YES), control returns to block1504. If, at block 1504, the next monitored media ratio does not matchthe corresponding ratio in the reference ratio signature (block 1504:NO), control proceeds to block 1510. At block 1510, the examplesignature comparator 222 utilizes a second level reference ratiosignature to match ratios in the monitored media ratio signature. Insome examples, the second level reference ratio signature includesratios defined as: dTr(n)/(dTr(n)+dTr(n+1)+dTr(n+2)). This is comparedto the monitored media ratio signature that includes ratios defined asdTm(n)/(dTm(n)+dTm(n+1)). An example ratio from an example second levelreference ratio signature at point dRr(2) would bedTr(2)/(dTr(2)+dTr(3)+dTr(4)) while a corresponding example ratio fromthe monitored media ratio signature at point dRm(2) would bedTm(2)/(dTm(2)+dTm(3)). In such an example, the monitored media deltadTm(3) is equal to dTr(3)+dTr(4).

The example second level reference ratio signature allows the examplesignature comparator 222 to identify a matching reference ratiosignature when the monitored media ratio signature has an error (e.g.,due to a missing energy peak in the monitored media signal). Additionallevels of ratios may be used to correct for additional errors, withoutdeparting from the scope of the present disclosure. Additionally,different ratio techniques may be combined with the additional levels ofratio signatures. Control then proceed to block 1508, and if there areno more ratios (block 1508: NO), the example instructions 1500 cease.

In some examples, the example monitored meter signal has extra peaks,which may affect the example monitored media deltas and/or ratios. Insuch examples, the example signature comparator 222 may utilize a firstlevel monitored media ratio signature to match ratios in the monitoredmedia ratio signature to reference ratio signatures. In some examples,the first level monitored media ratio signature includes ratios definedas: dTm(n)/(dTm(n)+dTm(n+1)). This is compared to a reference ratiosignature that includes ratios defined as dTr(n)/(dTr(n)+dTr(n+1)).Similarly as disclosed above, the example signature comparator 222 mayutilize a second level monitored media ratio signature to match ratiosin the monitored media ratio signature. In some examples, the secondlevel monitored media ratio signature includes ratios defined as:dTm(n)/(dTm(n)+dTm(n+1)+dTm(n+2)). This is compared to the referenceratio signature that includes ratios defined asdTr(n)/(dTr(n)+dTr(n+1)). An example ratio from an example second levelmonitored media ratio signature at point dRm(2) would bedTm(2)/(dTm(2)+dTm(3)+dTm(4)) while a corresponding example ratio fromthe reference ratio signature at dRr(2) would be dTr(2)/(dTr(2)+dTr(3)).In such an example, the reference delta dTr(3) is equal todTm(3)+dTm(4).

The example second level monitored media ratio signature allows theexample signature comparator 222 to identify a matching reference ratiosignature when the monitored media ratio signature has an error (e.g.,due to an extra energy peak in the monitored media signal). Additionallevels of ratios may be used to correct for additional errors, withoutdeparting from the scope of the present disclosure. Additionally,different ratio techniques may be combined with the additional levels ofratio signatures.

As disclosed above, missing and/or extra characteristics may appear inthe example reference media signal and/or the example monitored mediasignal. While the above example machine-readable instructions 1500 aredisclosed with respect to errors in the example monitored media signal(and thus the example monitored media delta and/or ratio signatures),these example instructions may be applied to the example reference mediasignal (and thus the corresponding example reference media delta andratio signatures) when missing and/or extra characteristics appear inthe example reference media signal.

FIG. 16 is a block diagram of an example processor platform 1600 capableof executing the instructions of FIGS. 12A-15 to implement the examplemedia manager 200 of FIG. 2 . The processor platform 1600 can be, forexample, a server, a personal computer, a mobile device (e.g., a cellphone, a smart phone, a tablet such as an iPad™), a personal digitalassistant (PDA), an Internet appliance, a DVD player, a CD player, adigital video recorder, a Blu-ray player, a gaming console, a personalvideo recorder, a set top box, or any other type of computing device.

The processor platform 1600 of the illustrated example includes aprocessor 1612. The processor 1612 of the illustrated example ishardware. For example, the processor 1612 can be implemented by one ormore integrated circuits, logic circuits, microprocessors or controllersfrom any desired family or manufacturer.

The processor 1612 of the illustrated example includes a local memory1613 (e.g., a cache). Additionally, the example processor 1612 mayfurther include the example media characterizer 206, the example deltacalculator 208, the example signature generator 210, the examplesignature receiver 218, the example delta extractor 220, the examplesignature comparator 222, the example media identifier 224, the examplemultiplier identifier 226, and the example media creditor 228.

The processor 1612 of the illustrated example is in communication with amain memory including a volatile memory 1614 and a non-volatile memory1616 via a bus 1618. The volatile memory 1614 may be implemented bySynchronous Dynamic Random Access Memory (SDRAM), Dynamic Random AccessMemory (DRAM), RAMBUS Dynamic Random Access Memory (RDRAM) and/or anyother type of random access memory device. The non-volatile memory 1616may be implemented by flash memory and/or any other desired type ofmemory device. Access to the main memory 1614, 1616 is controlled by amemory controller.

The processor platform 1600 of the illustrated example also includes aninterface circuit 1620. The interface circuit 1620 may be implemented byany type of interface standard, such as an Ethernet interface, auniversal serial bus (USB), and/or a PCI express interface.

In the illustrated example, one or more input devices 1622 are connectedto the interface circuit 1620. The input device(s) 1622 permit(s) a userto enter data and commands into the processor 1612. The input device(s)can be implemented by, for example, an audio sensor, a microphone, acamera (still or video), a keyboard, a button, a mouse, a touchscreen, atrack-pad, a trackball, isopoint and/or a voice recognition system.

One or more output devices 1624 are also connected to the interfacecircuit 1620 of the illustrated example. The output devices 1624 can beimplemented, for example, by display devices (e.g., a light emittingdiode (LED), an organic light emitting diode (OLED), a liquid crystaldisplay, a cathode ray tube display (CRT), a touchscreen, a tactileoutput device, a light emitting diode (LED), a printer and/or speakers).The interface circuit 1620 of the illustrated example, thus, typicallyincludes a graphics driver card, a graphics driver chip or a graphicsdriver processor.

The interface circuit 1620 of the illustrated example also includes acommunication device such as a transmitter, a receiver, a transceiver, amodem and/or network interface card to facilitate exchange of data withexternal machines (e.g., computing devices of any kind) via a network1626 (e.g., an Ethernet connection, a digital subscriber line (DSL), atelephone line, coaxial cable, a cellular telephone system, etc.).

The processor platform 1600 of the illustrated example also includes oneor more mass storage devices 1628 for storing software and/or data.Examples of such mass storage devices 1628 include floppy disk drives,hard drive disks, compact disk drives, Blu-ray disk drives, RAIDsystems, and digital versatile disk (DVD) drives.

The coded instructions 1632 of FIGS. 12A-15 may be stored in the massstorage device 1628, in the volatile memory 1614, in the non-volatilememory 1616, and/or on a removable tangible computer readable storagemedium such as a CD or DVD.

From the foregoing, it will be appreciated that the above disclosedmethods, apparatus, and articles of manufacture identify media bygenerating signatures that are unaffected by time-compression and/orplayback rate multipliers. Additionally, the above disclosed methods,apparatus, and articles of manufacture credit identified media for theamount of time the media would be presented if there were notime-compression and/or playback rate multipliers involved. This allowstime-compressed media and/or media with an increased playback rate to becredited in unison with media with a normal playback rate.

The disclosed methods, apparatus, and articles of manufacture solve aunique problem created by the use of time-compressed media andincreasing the rate of media playback. Although certain example methods,apparatus and articles of manufacture have been disclosed herein, thescope of coverage of this patent is not limited thereto. On thecontrary, this patent covers all methods, apparatus and articles ofmanufacture fairly falling within the scope of the claims of thispatent.

1. (canceled)
 2. An apparatus to identify media, the apparatuscomprising: interface circuitry; machine readable instructions; andprogrammable circuitry to at least one of instantiate or execute themachine readable instructions to: identify media characteristics of amonitored media signal; calculate respective time intervals betweencorresponding adjacent ones of the media characteristics; calculateratios of the time intervals; and generate a ratio signaturerepresentative of the monitored media signal, the ratio signaturegenerated based on the ratios.
 3. The apparatus of claim 2, wherein theprogrammable circuitry is to transmit the ratio signature to a mediamanager of an audience measurement entity via a network.
 4. Theapparatus of claim 2, wherein the programmable circuitry is to generatethe ratio signature based on a combination of a plurality of the ratiosdetermined for the monitored media signal.
 5. The apparatus of claim 4,wherein the programmable circuitry is to combine the plurality of theratios by combining a plurality of the time intervals determined for themonitored media signal.
 6. The apparatus of claim 2, wherein themonitored media signal is a time-compressed media signal from an outputdevice.
 7. The apparatus of claim 2, wherein the programmable circuitryis to identify the media characteristics by identifying temporalcharacteristics of the monitored media signal.
 8. The apparatus of claim2, wherein the programmable circuitry is to identify the mediacharacteristics by identifying local maximum points of a waveformassociated with the monitored media signal.
 9. An apparatus comprising:interface circuitry; computer readable instructions; and programmablecircuitry to at least one of instantiate or execute the computerreadable instructions to implement: a media characterizer to identifymedia characteristics of a monitored media signal; a delta calculatorto: calculate respective time intervals between corresponding adjacentones of the media characteristics; and calculate ratios of the timeintervals; and a signature generator to generate a ratio signaturerepresentative of the monitored media signal, the ratio signaturegenerated based on the ratios.
 10. The apparatus of claim 9, wherein thesignature generator is to transmit the ratio signature to a mediamanager of an audience measurement entity via a network.
 11. Theapparatus of claim 9, wherein the signature generator is to generate theratio signature by combining a plurality of the ratios determined forthe monitored media signal.
 12. The apparatus of claim 11, wherein thesignature generator is to combine the plurality of the ratios bycombining a plurality of the time intervals determined for the monitoredmedia signal.
 13. The apparatus of claim 10, wherein the monitored mediasignal is a time-compressed media signal from an output device.
 14. Theapparatus of claim 10, wherein the media characterizer is to identifythe media characteristics by identifying temporal characteristics of themonitored media signal.
 15. The apparatus of claim 10, wherein the mediacharacterizer is to identify the media characteristics by identifyinglocal maximum points of a waveform associated with the monitored mediasignal.
 16. A non-transitory machine readable storage medium comprisinginstructions to cause programmable circuitry to at least: identify mediacharacteristics of a monitored media signal; calculate respective timeintervals between corresponding adjacent ones of the mediacharacteristics; calculate ratios of the time intervals; and generate aratio signature representative of the monitored media signal, the ratiosignature generated based on the ratios.
 17. The non-transitory machinereadable storage medium of claim 16, wherein the instructions are tocause the programmable circuitry to transmit the ratio signature to amedia manager of an audience measurement entity via a network.
 18. Thenon-transitory machine readable storage medium of claim 16, wherein theinstructions are to cause the programmable circuitry to generate theratio signature by combining a plurality of the ratios determined forthe monitored media signal.
 19. The non-transitory machine readablestorage medium of claim 18, wherein the instructions are to cause theprogrammable circuitry to combine the plurality of the ratios bycombining a plurality of the time intervals determined for the monitoredmedia signal.
 20. The non-transitory machine readable storage medium ofclaim 16, wherein the instructions are to cause the programmablecircuitry to identify the media characteristics by identifying temporalcharacteristics of the monitored media signal.
 21. The non-transitorymachine readable storage medium of claim 16, wherein the instructionsare to cause the programmable circuitry to identify the mediacharacteristics by identifying local maximum points of a waveformassociated with the monitored media signal.